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Do Unvented Hot Water Cylinders Need Servicing?

Most people I meet believe that an unvented cylinder does not need servicing.

Most are unaware of a cylinder’s potential dangers, the majority that have been fitted have never been registered with the local council either.

Boom Boom Boom

Some unvented cylinders I see have the safety controls wired incorrectly and this could be a ticking time bomb.

All cylinders, if allowed to get in to the wrong condition, turn in to a bomb. If the cylinder is sealed, heat is continually added and uncontrolled, the pressure increases and boom! They can explode!

Building Control Notification

All new cylinders have to be notified to building control once they have been fitted.

Only qualifed engineers holding a current unvented hot water cylinder qualification are permitted, by law, to fit and service them.

The qualification only lasts 5 years, so if you are having a new cylinder fitted, ensure the engineer who turns up to install has a valid certificate.

Your families safety is in their hands, literally!

25 year Warranty, or No Warranty?

Most unvented cylinders come with a 25 year warranty.

If your cylinder has not been notified, fitted by a qualified engineer, or has not been serviced annually the cylinder manufacturer will not replace or repair the cylinder if something fails in the 25 years.

At the time of writing this article, I have recently replaced a 15 year old unvented cylinder that had rotted at the top, luckily it was only the outer shell. I contacted Kingspan, the manufacturer, to claim on behalf of the homeowner and the claim was refused as the cylinder had never been serviced, even though servicing wouldn’t have prevented the shell rotting.

So to summarise, unvented cylinders, if allowed to get in to a fault condition, act like a bomb. If you do not choose to have your cylinder serviced and something untoward does happen, not only would you have risked your families safety but you will not be covered under your insurance either, the first thing they will ask for is the service history.


Watch the below video to learn the shocking truth about cylinder manufacturers 25 year warranty.



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